
CAT28C256
32K-Bit Parallel E2PROM
FEATURES
■ Fast Read Access Times: 120/150ns
■ Low Power CMOS Dissipation:
–Active: 25 mA Max.
–Standby: 150 µA Max.
■ Simple Write Operation:
–On-Chip Address and Data Latches
–Self-Timed Write Cycle with Auto-Clear
■ Fast Write Cycle Time:
–5ms Max
■ CMOS and TTL Compatible I/O
DESCRIPTION
The CAT28C256 is a fast, low power, 5V-only CMOS
parallel E2PROM organized as 32K x 8-bits. It requires a
simple interface for in-system programming. On-chip
address and data latches, self-timed write cycle with autoclear and VCC power up/down write protection eliminate
additional timing and protection hardware. DATA Polling
and Toggle status bits signal the start and end of the selftimed write cycle. Additionally, the CAT28C256 features
hardware and software write protection.
■ Hardware and Software Write Protection
■ Automatic Page Write Operation:
–1 to 64 Bytes in 5ms
–Page Load Timer
■ End of Write Detection:
–Toggle Bit
–DATA Polling
■ 100,000 Program/Erase Cycles
■ 100 Year Data Retention
■ Commerical, Industrial and Automotive
Temperature Ranges
The CAT28C256 is manufactured using Catalyst’s advanced CMOS floating gate technology. It is designed to
endure 100,000 program/erase cycles and has a data
retention of 100 years. The device is available in JEDEC
approved 28-pin DIP, 28-pin TSOP or 32-pin PLCC
packages.
BLOCK DIAGRAM
A6–A
14
V
CC
CE
OE
WE
A0–A
5
© 1998 by Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
ADDR. BUFFER
& LATCHES
INADVERTENT
WRITE
PROTECTION
CONTROL
LOGIC
TIMER
ADDR. BUFFER
& LATCHES
ROW
DECODER
HIGH VOL TAGE
GENERAT OR
DATA POLLING
AND
TOGGLE BIT
COLUMN
DECODER
1
32,768 x 8
2
PROM
E
ARRAY
64 BYTE PAGE
REGISTER
I/O BUFFERS
I/O0–I/O
7
Doc. No. 25020-0A 2/98
5096 FHD F02

CAT28C256
PIN CONFIGURATION
PLCC Package (N)DIP Package (P)
V
A
A
OE
A
11
A
A
A
13
WE
CC
14
12
A
A
A
A
A
14
12
A
A
A
A
A
A
A
A
1
28
2
27
3
7
6
5
4
3
2
1
0
0
1
2
26
4
25
24
5
23
6
22
7
21
8
20
9
19
10
18
11
17
12
13
16
14
15
TSOP Package (8mm X 13.4mm) (T13)
V
CC
WE
A
13
A
8
A
9
A
11
OE
A
10
CE
I/O
I/O
I/O
I/O
I/O
A7A12A14NC
4321323130
A
A
A
A
A
A
A
7
NC
6
I/O
5
4
3
5
6
6
5
7
4
8
3
9
2
10
1
11
0
12
13
0
14 15 16 17 18 19 20
2
SS
I/O1I/O
NC
V
A
A
I/O
I/O
I/O
V
SS
1
2
9
8
3
4
5
6
7
8
9
7
6
5
4
3
10
11
12
13
14
13
VCCWE
A
29
28
27
26
25
24
23
22
21
5
I/O3I/O4I/O
28
27
26
25
24
23
22
21
20
19
18
17
16
15
A
8
A
9
A
11
NC
OE
A
10
CE
I/O
7
I/O
6
5096 FHD F01
A
CE
I/O
I/O
I/O
I/O
I/O
GND
I/O
I/O
I/O
A
A
A
10
7
6
5
4
3
2
1
0
0
1
2
PIN FUNCTIONS
Pin Name Function
A0–A
14
I/O0–I/O
7
Address Inputs
Data Inputs/Outputs
CE Chip Enable
OE Output Enable
Doc. No. 25020-0A 2/98
Pin Name Function
WE Write Enable
V
V
CC
SS
5V Supply
Ground
NC No Connect
2
28C256 F03

CAT28C256
ABSOLUTE MAXIMUM RATINGS*
Temperature Under Bias ................. –55°C to +125°C
Storage Temperature....................... –65°C to +150°C
Voltage on Any Pin with
Respect to Ground
VCC with Respect to Ground ............... –2.0V to +7.0V
Package Power Dissipation
Capability (Ta = 25°C)................................... 1.0W
(2)
........... –2.0V to +VCC + 2.0V
*COMMENT
Stresses above those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device.
These are stress ratings only, and functional operation
of the device at these or any other conditions outside of
those listed in the operational sections of this specification is not implied. Exposure to any absolute maximum
rating for extended periods may affect device performance and reliability.
Lead Soldering Temperature (10 secs) ............ 300°C
Output Short Circuit Current
(3)
........................ 100 mA
RELIABILITY CHARACTERISTICS
Symbol Parameter Min. Max. Units Test Method
N
T
V
I
LTH
END
DR
ZAP
(1)
(1)
(1)
(1)(4)
Endurance 104 or 10
Data Retention 100 Years MIL-STD-883, Test Method 1008
ESD Susceptibility 2000 Volts MIL-STD-883, Test Method 3015
Latch-Up 100 mA JEDEC Standard 17
5
Cycles/Byte MIL-STD-883, Test Method 1033
D.C. OPERATING CHARACTERISTICS
VCC = 5V ±10%, unless otherwise specified.
Limits
Symbol Parameter Min. Typ. Max. Units Test Conditions
I
CC
VCC Current (Operating, TTL) 30 mA CE = OE = VIL, f=8MH
z
All I/O’s Open
(5)
I
CCC
VCC Current (Operating, CMOS) 25 mA CE = OE = V
, f=8MH
ILC
z
All I/O’s Open
I
SB
I
SBC
(6)
VCC Current (Standby, TTL) 1 mA CE = VIH, All I/O’s Open
VCC Current (Standby, CMOS) 150 µA CE = V
IHC
,
All I/O’s Open
I
LI
I
LO
(6)
V
IH
(5)
V
IL
V
OH
V
OL
V
WI
Note:
(1) This parameter is tested initially and after a design or process change that affects the parameter.
(2) The minimum DC input voltage is –0.5V. During transitions, inputs may undershoot to –2.0V for periods of less than 20 ns. Maximum DC
voltage on output pins is VCC +0.5V, which may overshoot to VCC +2.0V for periods of less than 20 ns.
(3) Output shorted for no more than one second. No more than one output shorted at a time.
(4) Latch-up protection is provided for stresses up to 100mA on address and data pins from –1V to VCC +1V.
(5) V
(6) V
= –0.3V to +0.3V.
ILC
= VCC –0.3V to VCC +0.3V.
IHC
Input Leakage Current –10 10 µAVIN = GND to V
Output Leakage Current –10 10 µAV
= GND to VCC,
OUT
CE = V
IH
High Level Input Voltage 2 VCC +0.3 V
Low Level Input Voltage –0.3 0.8 V
High Level Output Voltage 2.4 V IOH = –400µA
Low Level Output Voltage 0.4 V IOL = 2.1mA
Write Inhibit Voltage 3.5 V
CC
3
Doc. No. 25020-0A 2/98